Treatment of coffee.



TED sTAtrEsPAT-ENT OFFICE.

JOHANN FRIEDRIGiEi MEYER, Ht, LUDWIG ROSELIUS, AND KARL WIMMER, 0F BREMEN,

' i GERMANY.

THE ATMENIT OF COFFEE.

Application fi1ed. May 4, 1906. Serial No, 815,181. (Specimens) To all whom it may concern:

residing at Bremen, Germany,- have invented certain new and useful Improvements Relating to the Pro aration or'Treatment of Cofl'e'e, of which t 1e following is a specification. 1 This invention. relates to a process for treating coffee and the object thereof is to rovide a process in a manner as hereinafter set forth forfextracting caffcin from crude and unbroken green coifee beans, without materially impairing the aromatic constituents of the coffee. 7

Attempts heretofore made for extracting from green-unbroken beans c'afi'ein, without injuring the bean in other respects, have not been successful, chiefly because the extracting medium reniov es from the coffee not only the caifein, but also other aromatic constitusolution is supplied to the a ,nor to render ibunsalable for roasting.

' fatty ents', some of-'which are valuable, and be cause it ll&S"I16i7:-bQ-ED J QQII practicable to dry the wet and swollenupbeansinsuch a manner as y The foregoing objections are overcome by a process -1I1 accordance with this invention, in which the extraction of the cafi'ein, the restoration to the coffee of the valuable constituents dissolved along with the caifein and the drying of the coffee takes lace in vacuo.

The crude and un roken green coffee beans are first placed in a vacuum apparatus, after which the extracting medium, such as water, a volatile solvent, acid or an alkali paratus. The vacuum is then broken in on er to facilitate the penetration of the extracting li uid into the cells of the beans, after which t 1e vacuum is again established and the green beans subjected to extract-ion whereby the green beans are deprived of cafl'ein and the other constituents, such as the aromatic oils and substances removed. When the extraction is completcd'the solution containing the cafl'ein and other constituents is removed, the beans still remaining under a vacuum. The solution is then treated in a known manner so as to deprive it of cailein. The green beans are then subi'eeted to the'solution containing all the va uable constituents with the exception of the cafiein. By such impregnation step to neither affect its appearance,

a remaining in vacuo walled ce steps the beans areim'pregnated with the said constituents, the beans remaining under vacuum during. this 'ste but-during said the beans are stirred. 'After the solution has been uniformly distributed o'vcrthe beans the vacuum is-interrupted for a short time in order to facilitate the penetration of the solution into the cells, after which the vacuum is reestablished and the green beans are dried at-a moderate temperature.

As more specifically setting forth a process of treating reen coffee beans, reference is had to the fo lowing example: 1() kilograms of crude and unbroken green coffee beans are placed in a vacuum pan, 'wa-tcr is then admitted until the beansare well covered with Patented Sept. 1, 1908.

it, the vacuum is interrupted for about 5 to 10 minutes, then restored andthe beans sub- 'ected to extraction for from two' to three ours atnbout 40 to 50 The extract thus obtained is treated with a minute quantity of ammoniain order tofl dccompose the salts of cail'ein, after which the free caiieinis washed out with chloroform or benzene. When the chloroform adhering to the residue has-evaporated, the residue is dissolved in about l*liter 0f water. Th beans after the solution containiin the extract has been withdrawn are stilhin 'vacuo. While the beans are in this state the-solution is added thereto and the beans are m oistened while stirred. After the solution has been uniformly distributed over the green beans, the vacuum is' interrupted for a .short time in order to facilitate tho iinpregnation of the aromatic constituents in the beans, after which the vacuum is reestablished and the green unaltered beans dried at a moderate tom )erature. Ti advantages :()wmg totliense of a vacuum the coffee may proccss at a low tcmperature,:the extracting medium 'ienctrat'cs easily into the thickest v ils and thewhole of the constituents of the coffee with the exception of caii'ein arc retained without any material alteration owing to the f act that during the concentration of the extract at a low'tcm pcrature the distilled aromatic substances remain in the extract and any change of the sugar 1H 10 foregoing process oif ers the following' be treated throughout the and at the samecjtime avoided. 'lhc impregnation with the solution reaches the innermost cells, and the rapid drying-at a low temperature prevents the beanstrom shrinking and becoming black,

but more particularly the process is such that it does not injuriously affect the taste of the cofi'ee.

l. Ina process for obtaining green unbroken cofiee beans freed of cafi'eiu, subjecting the unbroken green cofiee beans to extraction in vacuo, removing the extract, depriving the extract of eafi'ein, redissolvingthe residue and restoring it to the green beans while iflvacuo, interrupting the vacuum for a short period and then restoring the vacuum, and then drying the impregnated green beans in racuo. I

2. In a process for obtaining green unbroken coflee beans freed of caffein, subjecting the green beans to extraction in CHOU-0, drawin off the liquid extract, removing the cafi'ein 'rom said extract, and then adding to the beans Whilev in vacuo the said extract -freed of cafl'ein whereby the green beans are impregnated with said extract.

3. In a process for obtaining green unbroken cofi'ee beans freed of cafi'ein, subjecting the green beans to extraction in *vacuo, drawing off the liquid extract, removing the caii'ein from said extract, then adding to the beans while in vacuo the said extract freed of caflein whereby the green beans are impregtemperature.

In testimony whereof we have set our hands hereunto in presence of two subscribing witnesses. I JOHANN FRIEDRICH MEYER, JR. LUDWIG ROSELIUS.

nit WIMMER.

Witnesses:

(I. DIEDRICII, FIIIoYEmuANN.

nated with said extract, and then drying the impregnated beans m cacao at a moderate 

